<template>
  <view v-if="show" class="u-notice-bar" :style="{
      background: computeBgColor,
      padding: padding,
    }" :class="[type ? `u-type-${type}-light-bg` : '']">
    <view class="u-direction-row">
      <view class="u-icon-wrap">
        <view v-if="volumeIcon" class="u-left-icon">关注</view>
        <!-- <u-icon
          class="u-left-icon"
          v-if="volumeIcon"
          name="volume-fill"
          :size="volumeSize"
          :color="computeColor"
        ></u-icon> -->
      </view>
      <view class="u-notice-box" id="u-notice-box">
        <view class="u-notice-content" id="u-notice-content" :style="{
            animationDuration: animationDuration,
            animationPlayState: animationPlayState,
          }">
          <text class="u-notice-text" @tap="click" :style="[textStyle]"
            :class="['u-type-' + type]">{{ showText }}</text>
        </view>
      </view>
      <view class="u-icon-wrap">
        <u-icon @click="getMore" class="u-right-icon" v-if="moreIcon" name="arrow-right" :size="26"
          :color="computeColor"></u-icon>
        <u-icon @click="close" class="u-right-icon" v-if="closeIcon" name="close" :size="24"
          :color="computeColor"></u-icon>
      </view>
    </view>
  </view>
</template>
<script>
export default {
  props: {
    // 显示的内容，数组
    list: {
      type: Array,
      default() {
        return [];
      },
    },
    // 显示的主题，success|error|primary|info|warning|none
    // none主题默认为透明背景，黑色(contentColor)字体
    type: {
      type: String,
      default: 'warning',
    },
    // 是否显示左侧的音量图标
    volumeIcon: {
      type: Boolean,
      default: true,
    },
    // 是否显示右侧的右箭头图标
    moreIcon: {
      type: Boolean,
      default: false,
    },
    // 是否显示右侧的关闭图标
    closeIcon: {
      type: Boolean,
      default: false,
    },
    // 是否自动播放
    autoplay: {
      type: Boolean,
      default: true,
    },
    // 文字颜色，各图标也会使用文字颜色
    color: {
      type: String,
      default: '',
    },
    // 背景颜色
    bgColor: {
      type: String,
      default: '',
    },
    // 是否显示
    show: {
      type: Boolean,
      default: true,
    },
    // 字体大小，单位rpx
    fontSize: {
      type: [Number, String],
      default: 26,
    },
    // 音量喇叭的大小
    volumeSize: {
      type: [Number, String],
      default: 34,
    },
    // 水平滚动时的滚动速度，即每秒滚动多少rpx，这有利于控制文字无论多少时，都能有一个恒定的速度
    speed: {
      type: [Number, String],
      default: 160,
    },
    // 播放状态，play-播放，paused-暂停
    playState: {
      type: String,
      default: 'play',
    },
    // 通知的边距
    padding: {
      type: [Number, String],
      default: '18rpx 10rpx',
    },
  },
  data() {
    return {
      textWidth: 0, // 滚动的文字宽度
      boxWidth: 0, // 供文字滚动的父盒子的宽度，和前者一起为了计算滚动速度
      animationDuration: '10s', // 动画执行时间
      animationPlayState: 'paused', // 动画的开始和结束执行
      showText: '', // 显示的文本
    };
  },
  watch: {
    list: {
      immediate: true,
      handler(val) {
        this.showText = val.join('，');
        this.$nextTick(() => {
          this.initSize();
        });
      },
    },
    playState(val) {
      if (val == 'play') this.animationPlayState = 'running';
      else this.animationPlayState = 'paused';
    },
    speed(val) {
      this.initSize();
    },
  },
  computed: {
    // 计算字体颜色，如果没有自定义的，就用uview主题颜色
    computeColor() {
      if (this.color) return this.color;
      // 如果是无主题，就默认使用content-color
      else if (this.type == 'none') return '#606266';
      else return this.type;
    },
    // 文字内容的样式
    textStyle() {
      let style = {};
      if (this.color) style.color = this.color;
      else if (this.type == 'none') style.color = '#606266';
      style.fontSize = this.fontSize + 'rpx';
      return style;
    },
    // 计算背景颜色
    computeBgColor() {
      if (this.bgColor) return this.bgColor;
      else if (this.type == 'none') return 'transparent';
    },
  },
  mounted() {
    this.$nextTick(() => {
      this.initSize();
    });
  },
  methods: {
    initSize() {
      let query = [],
        boxWidth = 0,
        textWidth = 0;
      let textQuery = new Promise((resolve, reject) => {
        uni
          .createSelectorQuery()
          .in(this)
          .select(`#u-notice-content`)
          .boundingClientRect()
          .exec((ret) => {
            this.textWidth = ret[0].width;
            resolve();
          });
      });
      query.push(textQuery);
      Promise.all(query).then(() => {
        // 根据t=s/v(时间=路程/速度)，这里为何不需要加上#u-notice-box的宽度，因为中设置了.u-notice-content样式中设置了padding-left: 100%
        // 恰巧计算出来的结果中已经包含了#u-notice-box的宽度
        this.animationDuration = `${this.textWidth / uni.upx2px(this.speed)}s`;
        // 这里必须这样开始动画，否则在APP上动画速度不会改变(HX版本2.4.6，IOS13)
        this.animationPlayState = 'paused';
        setTimeout(() => {
          if (this.playState == 'play' && this.autoplay)
            this.animationPlayState = 'running';
        }, 10);
      });
    },
    // 点击通告栏
    click(index) {
      this.$emit('click');
    },
    // 点击关闭按钮
    close() {
      this.$emit('close');
    },
    // 点击更多箭头按钮
    getMore() {
      this.$emit('getMore');
    },
  },
};
</script>

<style lang="scss" scoped>
@import '../../libs/css/style.components.scss';

.u-notice-bar {
  padding: 18rpx 24rpx;
  overflow: hidden;
}

.u-direction-row {
  @include vue-flex;
  align-items: center;
  justify-content: space-between;
}

.u-left-icon {
  /* #ifndef APP-NVUE */
  display: inline-flex;
  /* #endif */
  align-items: center;
  width: auto;
  height: 32rpx;
  padding: 0 8rpx;
  line-height: 32rpx;
  font-size: 22rpx;
  font-weight: bold;
  color: #f36b40;
  background-color: #ffddd1;
  border-radius: 6rpx;
  text-align: center;
}

.u-notice-box {
  flex: 1;
  @include vue-flex;
  overflow: hidden;
  margin-left: 12rpx;
}

.u-right-icon {
  margin-left: 12rpx;
  display: inline-flex;
  align-items: center;
}

.u-notice-content {
  animation: u-loop-animation 10s linear infinite both;
  text-align: right;
  // 这一句很重要，为了能让滚动左右连接起来
  padding-left: 100%;
  @include vue-flex;
  flex-wrap: nowrap;
}

.u-notice-text {
  font-size: 26rpx;
  word-break: keep-all;
  white-space: nowrap;
}

@keyframes u-loop-animation {
  0% {
    transform: translate3d(0, 0, 0);
  }

  100% {
    transform: translate3d(-100%, 0, 0);
  }
}
</style>
